Jack Boelte

My 2006 C6 M6 is giving me some trouble - sometimes - when I do hard acceleration. It seems like it's running out of gas in the high RPMs. It pulls hard to around 5K, then total power loss. I've always let up on the throttle, so I don't know if it picks back up. Usually I upshift and the power is back, until 5K. I'm doing this on the street, so I haven't pushed it too far. It doesn't do it all of the time. Many times I can accelerate at WOT with no issues. BTW, the car has about 85,000 miles.

I'm thinking I might have a clogged fuel filter, weak pump, or failing fuel pressure regulator. I have an Actron CP9580 Autoscanner Plus code reader. I'm going to see if it will pull any useful data.

Does anyone have any suggestions?

Mike's LS3

I would put a fuel pressure gauge on the fuel rail with a long enough fuel line to secure the gauge onto your wiper to read the gauge at WOT . Quickly, glance at your fuel pressure at 5k and see what happens. If pressure drops significantly, chances are you fuel pump is failing. Idle fuel pressure is around 58 - 62 psi. At WOT, I believe fuel pressure should maintain 55 + psi. If the fuel pump needs replacement, I would have the C6 Z06 fuel pump installed.

BTW: The fuel pressure hose screws into the Schrader valve at the end of the fuel rail. Remove the black cap at the end of the fuel rail and screw the fuel line with the proper Schrader valve adapter for GM. Use tie wraps to secure and route the fuel line safely away from any moving parts or hot engine components. Make sure you use proper fittings and only fuel line to extend the gauge for viewing. I also leave the hood unlatched on the drivers side making sure you do not pinch the fuel line in any way. Use caution and common sense when dealing with fuel!

Jack Boelte

Thanks Mike! I was hoping the scan tool might capture fuel pressure. If I can't figure out how to capture it I'll use your idea. Thanks again!

jim2092

Had a similar problem with my highly modified 2005 C6. While on a dyno for a tune, it started showing lean AFR at higher RPMs. A fuel pressure gauge attached to the fuel rail showed declining fuel pressure at higher RPMs. A new ZO6 fuel pump solved the problem. All this much easier to do on a dyno but more costly.

Jack Boelte

Yeah, I was thinking a dyno would be the way to go. With 85,000 miles it might be safe to assume it's time to upgrade to the Z06 pump, along with filter and fuel gage sending unit...

I'll still do more trouble shooting before I buy anything...

tblu92

Sound like your car is basically STOCK---There would be no reason then a stock fuel pumps should NOT be adequate-----sounds like you simply have a clogged or old fuel filter--I would deff change it---

2nd---- A common issue----IF you have a cold air intake that utilizes an "oiled" filer element--this has become a huge issue--so much that the new trend is to go to a synthetic paper OILESS filter design--- Oiled filters when 1st installed tend to allow the excess oil to be sucked into your MAF sensor and permanently fouling it as the oil residue burns onto the MAF wires and it will never read correctly again----You should try to clean your MAF and see if this helps----also other issues can cause your MAF to foul-like extreme water intrusion in the intake----A fouled MAF or even a bad MAF will create your same power loss above 5000----I would check this 1st--change the filter before doing anything more extreme---